MRegTest: A Replay-Based Regression Testing Tool for Distributed UML-RT Models

Regression testing is indispensable, especially for real-time distributed systems to ensure that existing functionalities are not affected by changes. In this paper, we present MRegTest, a replay-based regression testing tool for distributed systems that are developed using communicating state machine models. Despite recent advances, regression testing for distributed systems remains challenging. The inherent non-determinism typically allows systems to exhibit many different executions in response to the same input. In addition, it is often not possible to control the execution environment such that this non-determinism is removed without changing the execution semantics. MRegTest addresses the above-mentioned challenges via Automatic Mutant Generation (AMG) and Regression Testing (RT) modules. AMG facilitates regression testing by generating several mutants from a UML-RT model according to a user-defined set of critical variables. RT allows the user to detect regressions of both single or multiple modified models. It then reports regressions and enables the user to replay traces visually in a web-based application. We have evaluated MRegTest against several use cases with various complexities. The experimental results show that compared to the traditional approaches that annotate traces with timestamps and variable values MRegTest detects almost all regressions while reducing the size of the trace significantly. The tool demonstration video: https://youtu.be/lPXjmKgadQI